Color photographic layers comprising non-diffusible 5-hydroxycoumarans as stabilizing compounds

ABSTRACT

NONDIFFUSIBLE 5-HYDROXYCOURMARAN STABLIZER COMPOUNDS WHICH HAVE EITHER A SUBSTITUTED AMINO GROUP OR AN ALKOXY GROUP SUBSTITUTED ON THE CARBON ATOMS IN THE 2 POSITION ARE ADVANTAEOUSLY INCORPORATED IN HYDROPHILIC COLLOID LAYERS OF PHOTOGRAPHIC ELEMENTS IN WHICH COLOR PHOTOGRAPHIC DYE IMAGES ARE TO BE STORED FOR VIEWING. THE STABLIZER COMPOUNDS PROTECT DYE IMAGES AGAINST THE FADING EFFECTS OF PROLONGED EXPOSURE TO LIGHT.

United States Patent 3,573,050 COLOR PHOTOGRAPHIC LAYERS COMPRISING NON-DIFFUSIBLE 5 HYDROXYCOUMARANS AS STABILIZING COMPOUNDS Kent C. Brannock, Kingsport, Tenn., and Gregory J. Lestina, Rochester, N.Y., assignors to Eastman Kodak Company, Rochester, N.Y. No Drawing. Filed Feb. 27, 1969, Ser. No. 803,080 Int. Cl. G03c 1/84, N40 US. C]. 96-84 16 Claims ABSTRACT OF THE DISCLOSURE Nondiffusible S-hydroxycoumaran stabilizer compounds which have either a substituted amino group or an alkoxy group substituted on the carbon atoms in the 2 position are advantageously incorporated in hydrophilic colloid layers of photographic elements in which color photographic dye images are to be stored for viewing. The stabilizer compounds protect dye images against the fading effects of prolonged exposure to light.

This invention relates to photography, photographic materials including color photographic materials containing dye image stabilizing agents, and methods for improving the stabilities of dyes in photographic materials.

The formation of dye images by the chromogenic development of silver halide photographic materials, involving the coupling reaction of oxidized primary aromatic amino developing agents with coupling compounds to form indophenol, indamine, azomethine, phenoxazine, phenazine, and similar dyes, is well known. In this system, the subtractive color process of color formation is ordinarily used and the image dyes customarily formed are cyan, magenta, and yellow, which are the colors that are complementary to the primary colors, red, green and blue, respectively. Usually phenolic couplers (i.e., phenols and naphthols) are used to form the cyan dye image; pyrazolone or cyanoacetyl couplers are used to form the magenta dye image; and acylacetamide or dibenzoylmethane couplers are used to form the yellow dye image.

In these color photographic systems, the color-forming coupler may be applied in a developer solution or incorporated in the light-sensitive photographic emulsion layer or in another dye-image-forming layer, so that, during development, it is available to react with oxidized color developing agent formed as the result of latent image development.

The dye images formed in such processes are not indefinitely stable to ultraviolet radiation so that under rigorous viewing or display conditions involving, for example, long periods of exposure to sunlight, or other ultraviolet radiant illumination, the dyes may fade, resulting in deterioration in the quality of the picture.

Increases in the stability of indophenol, indoaniline, and azomethine dyes to ultraviolet radiation have been achieved by the use of a variety of agents which can be added to the emulsion in processing, or more conveniently, in manufacture. Lestina and Reckhow describe the use of dinuclear 6-hydroxy chroman stabilizers in photographic elements in US. Ser. No. 452,889, filed May 3, 1965 now US. Pat. No. 3,432,300. The need remains for still other stabilizers that will further enhance the resistance of these dyes to actinic light.

It is therefore an object of our invention to provide novel photographic elements containing dyes and/ or dyeforming compounds, and S-hydroxycoumaran stabilizer compounds to increase the stability of the dyes against ultraviolet and visible light radiation.

Another object of our invention is to provide novel image dye stabilizing agents which do not form highly Patented Mar. 30, 1971 colored oxidation products in the processing baths, e.g., bleach baths, etc., used in color photographic processing.

Another object of our invention is to provide novel color photographic image-forming layers comprising hydrophilic colloid film-forming binders containing finely particulate dispersions of solutions of our S-hydroxycoumaran stabilizing agents.

It is a further object to provide such layers also containing couplers.

A further object is to provide novel dispersions of our S-hydroxycoumaran stabilizing agents which can be incorporated in silver halide emulsion layers without adverse emulsion effects.

It is a still further object of our invention to provide novel processed color photographic layers containing dye images in association with the S-hydroxycoumaran stabilizing agents of our invention.

These and other objects will be apparent from a consideration of the following specification and claims.

These and other objects are accomplished according to our invention by providing hydrophilic colloid layers for the storage of dye images that are stabilized against the effects of prolonged exposure to light by the incorporation of a nondifiusible S-hydroxycoumaran, such as, a 2-amino-S-hydroxycoumaran and a 2-alkoxy-5-hydroxycoumaran. Our stabilizing compounds are particularly advantageous for the stabilization of indophenol dye images, indoaniline dye images, azomethine dye images and azo dye images that are stored in hydrophilic colloid layers for viewing. These dye images are either formed as nondilfusible dye images in the hydrophilic colloid layer containing our stabilizer compound or are formed as diffusible dye images in another hydrophilic colloid layer and transferred to a receiving layer containing a hydrophilic colloid layer with our stabilizer compound. Our invention provides valuable technical advances.

Our nondiifusible S-hydroxycoumaran stabilizing compounds include those represented by the formula:

wherein R represents hydrogen, an alkyl group, preferably an alkyl group having from 1 to 22 carbon atoms (e.g., methyl, ethyl, isopropyl, butyl, t-butyl, cyclohexyl, octyl, t-octyl, dodecyl, octadecyl, docosyl, etc.) and the atoms necessary to complete with R a fully hydrogenated hydrocarbon ring of 4 to 7 atoms, preferably 5 to 6 atoms in the ring (e.g., cyclobutane, cyclopentane, cyclohexane, cycloheptane, etc.); R represents an alkyl group having from 1 to 22 carbon atoms as described for R and the atoms necessary to complete with R a fully hydrogenated hydrocarbon ring of 4 to 7 atoms, preferably 5 to 6 atoms in the ring (e.g., cyclobutane, cyclopentane, cyclohex'ane, cycloheptane, etc.); R represents hydrogen, an alkyl group, preferably having from 1 to 22 carbon atoms, such as have been described for R and an al'koxy group having from 1 to 22 carbon atoms (e.g., methoxy, propoxy, t-butoxy, hexoxy, 2-methylpentyl0xy, dodecoxy, octadecoxy, docosoxy, etc.; 01., represents hydrogen, an alkyl group having from 1 to 22 carbon atoms and preferably a branched chain alkyl group (e.g., methyl, isopropyl, t-butyl, Z-methylpentyl, 2,2-dimethylpentyl, t-octyl, dodecyl, octadecyl, docosyl, etc.), an alkoxy group having from 1 to 22 carbon atoms as described for R and the atoms necessary to complete with R a 5, 6 or 7 membered carbocyclic ring, such as, a cyclopentane ring (e.g., cyclopentane methylcyclopentane, methoxycyclopentane, etc.), a cyclohexane ring (e.g., cyclohexane, ethylcyclohexane, ethoxycyclohexane, w-hydroxyhexylcyclohexane, etc.) and a cycloheptane ring (e.g., cycloheptane, ethylcycloheptane, methoxycycloheptane, w-hydroxybutoxy cycloheptane, etc.); R represents hydrogen, an alkyl group having from 1 to 22 carbon atoms at described for R a mononuclear aryl group (e.g., phenyl, tolyl, ethylphenyl, etc.), an. alkoxy group having from 1 to '22 carbon atoms as has been described for :R and the atoms necessary to complete with R, a 5, 6 or 7 membered carbocyclic ring, such as, a cyclopentane ring (e.g., cyclopentane, methylcyclopentane, methoxycyclopentane, etc.), a cyclohexane ring (e.g., cyclohexane, ethylcyclohexane, ethoxycyclohexane, w-hydroxyhexylcyclohexane, etc.) and a cycloheptane ring (e.g., cycloheptane, ethylcycloheptane, rnethoxycycloheptane, w hydroxybutoxycycloheptane, etc.); Z represents a Rs N group or a OR group; R represents an alkyl group, preferably an alkyl group of from 1 to 22 carbon atoms (e.g., methyl, isopropyl, t-butyl, 2-methylpentyl, 2,2-dimethylpentyl, t-octyl, dodecyl, octadecyl, docosyl, 2,3- pentenyl, 3,4-pentenyl, 2-hydroxyethyl, 2-ch1oroethyl, 2- carboxyethyl, 3-sulfopropyl, 2-cyanoethyl, 2-nitroethyl, 4- nitrobutyl, cyclobutyl, cyclopentyl, cyclohexyl, 2-methy1- cyclohexyl, cycloheptyl, etc.), an aryl group, such as, a phenyl group (e.g., phenyl, ptolyl, o-tolyl, o-ethylphenyl, p-isopropylphenyl, etc.), a naphthyl group (e.g., a-naph thyl, 2-methyl-a-naphthyl, B-naphthyl, etc.), a heterocyclic group having from 4 to 7 and preferably 5 to 6 atoms in the heterocyclic ring (e.g., pyridyl, quinolyl, thiazolyl, benzothiazolyl, naphthothiazolyl, oxazolyl, benzoxazolyl, imidazolyl, benzimidazolyl, etc.), and the atoms necessary to complete with R; a heterocyclic ring having from 4 to 7 atoms and preferably 5 to 6 atoms in the ring (e.g., piperidino, morpholino, thiamorpholino, pyrrolidinyl, etc.); R7 represents an alkyl group preferably an alkyl group of from 1 to 22 carbon atoms (e.g., methyl, isopropyl, t butyl, 2-methylpentyl, 2,2-dimethylpentyl, t-octyl, dodecyl, octadecyl, docosyl, 2,3-pentenyl, 3,4- pentenyl, 2-hydroxyethyl, 2-chloroethyl, 2-carboxyethyl, 3-sulfopropyl, 2-cyanoethyl, 2-nitroethy1, 4-nitrobutyl,

cyclobutyl, cyclopentyl, cyclohexyl, 2-methylcyclohexyl, cycloheptyl, etc.), an aryl group, such as, a phenyl (e.g., phenyl, p-tolyl, o-tolyl, o-ethylphenyl,

p-isopropylphenyl, etc.), a naphthyl group, e.g., ot-naphthyl, 2-methyl-a-naphthyl, fl-naphthyl, etc.), a heterocyclic group having from 4 to 7 and preferably 5 to 6 atoms in the heterocyclic ring (e.g., pyridyl, quinolyl, thiazolyl, benzothiazolyl, naphthothiazolyl, oxazolyl, benzoxazolyl, imidazolyl, benzimidazolyl, etc.), and the atoms necessary to complete with R a heterocyclic ring having from 4 to 7 atoms and preferably 5 to 6 atoms in the ring (e.g., piperidino, morpholino, thiamorpholino, pyrrolidinyl, etc.); and R represents an alkyl group having from 1 to 22 carbon atoms as has been described for the alkyl group under R and R Included among the compounds of Formula I that are used advantageously according to our invention are the following typical compounds:

(1) 6 t-butyl-3,3-dimethyl-S-hydroxy-Z-morpholinocoumaran (2) 6 t butyl-3,3-dimethyl-2-(N-ethoxycarbonyl-N- piperazino)-5-hydroxycoumaran (3) 6 t butyl-3-butyl3-ethyl-5-hydroxy-2-piperadino coumaran (4) 3,3-dimethyl 5 hydroxy-2-(N-methylanilino)-6-toctylcoumaran (5) 5-hydroxy 2 (N-butylanilino)-3-methyl-6-t-octy1- coumaran (6) 3,3-dimethyl 5 hydroxy-(N-methylanilino)-6-toctoxycoumaran (7) 6 t butyl-3,3-dimethy1-5-hydroxy-2-(N-methylanilino) coumaran (8) 6 t butyl-3,3-dimethyl-2-(3-ethoxycarbonylpiperidino)-5-hydroxycoumaran (9) 3,3-dibuty1 5 hydroxy-Z-(N-methylanilino)-6-toctylcoumaran (10) 6 t butyl-3,3-dibutyl-5-hydroxy-2-(N-methylanilino)coumaran (11) 3-butyl 3 ethyl-5-hydroxy-2-(N-methylanilino)- 6-t-octylcoumaran (12) 3,3-dimethyl 5 hydroxy-2-(N-methyl-N-hexylamino) -6-t-octylcoumaran (13) 3,3-dimethyl 5 hydroxy-2,6-t-octyl piperidinocoumaran (14) 6 t butyl-3,3-dimethyl-5-hydroXy-2-(N-methyl- N-octadecylamino) coumaran (15) Z-(N-anilino) 6 t butoXy-5-hydroXy-3,3,4-trimethylcoumaran (16) 7 t butyl-3,3-dimethyl-4-ethoxy-5-hydroxy-Z-(N- methylanilino) coumaran (l7) 6-t-butyl-3,3-dimethyl-5-hydroxy-2- (N-methylanilino -7-phenylcoumaran 18) 6-t-butyl-3,3-dimethyl-7-ethoxy-S-hydroxy-Z- (N-methylanilino coumaran (19) 3,3-dimethyl-2- (N,N-dimethylamino) -5-hydroxy- 6,7,8,9-tetrahydrobenzocoumaran (20) 6-t-butyl-3,3-dimethyl-2-ethoXy-5- hydroxycoumaran (21 3-butyl-2-ethoxy-3-ethyl-5-hydroxy- 5-t-octylcoumaran (22) 3 ,3 -dimethyl-2-ethoxy-5-hydroxy-6-t-octylcoum aran (23) 2-butoxy-6-t-butyl-3,3-dimethyl-5-hydroxycoumaran (24) 6-t-butyl-3,3-dimethyl-S-hydroxy-Z-octadecyloxycoumaran (25) 6-t-butyl-3,3-dimethyl-2-docosoXy-5-hydroxycoumaran (26) 6-t-butyl-3,3-dimethyl-5-hydroXy-2-(Z-methylpentoxy) coumaran Our stabilizing agents are advantageously used to improve the stability of the indophenol, indoaniline and azomethine dyes, such as, those produced by chromogenic development, the azo dyes produced in Well-known diazotype elements, and dyes produced in well-known silver-dyemethod used to form the indophenol, indoaniline, azomethine, or azo dye is not important since any of the well-known image-forming elements and processes are used advantageously.

Our stabilizers are particularly eflicacious in protecting dyes produced by chromogenic development of any of the well-known 5-pyrazolone couplers used in photography for magenta dye formation. Typical magenta dyes are those produced by color development of couplers described in U.S. patents, such as, 2,600,788, 2,725,292, 2,908,573, 3,006,759, 3,062,653, 3,152,896, 3,311,476 and Young U.S. application Ser. No. 458,455, filed May 24, 1965, now U.S. Pat. No. 3,419,391, which couplers are herein incorporated by reference.

Cyan dye-forming couplers of such U.S. patents as 2,474,293, 2,725,292, 2,895,826, 2,908,573 produce cyan dyes upon chromogenic development that are advantageously stabilized against light exposure by our stabilizing compounds.

Yellow dye-forming couplers of U.S. Pat. 2,908,573 produce yellow dyes that are made less subject to the fading effects of prolonged exposure to light by the presence of our stabilizing compounds.

Our stabilizing agents are incorporated alone or together with a color-forming coupler in a dye image-forming layer of a color photographic element. A useful methd of dispersing our stabilizing compounds is that described for dispersing couplers in Mannes et al. U.S. Pat. 2,304,939, issued Dec. 15, 1942; Jelley et al. U.S. Pat. 2,322,027, issued June 15, 1943, etc., in which high-boiling organic solvents are used to dissolve the material. Other applicable methods are described in Vittum et al. U.S. Pat. 2,801,170, and Fierke et al. U.S. Pat. 2,801,171, both issued July 30, 1957, and Julian U.S. Pat. 2,949,360, issued Aug. 16, 1960, in which low-boiling or watersoluble organic solvents are used with high-boiling solvent.

In these methods of dispersion our stabilizing agents can be contained in the same dispersion with nondifiusing couplers, or in a separate dispersion, and the couples can optionally be dispersed directly in the emulsion. Highboiling solvents useful in dispersing the -hydroxycoumaran stabilizer compounds of our invention include di-nbutylphthalate, benzylphthalate, triphenyl phosphate, tri-ocresyl phosphate, diphenyl mono-p-tert-butylphenyl phosphate, monophenyl di-p-tert-butylphenyl phosphate, diphenyl mono-o-chlorophenyl phosphate, monophenyl dio-chlorophenyl phosphate, tri-p-tert-butylphenyl mono(5- tert-butyLZ-phenylphenyl)phosphate, 2,4 di n-amylphenol, 2,4-di-t-amylphenol, N,N-diethylauramide, etc.

The low-boiling or water-soluble organic solvents which can be used to advantage with the high-boiling solvents are disclosed in patents, such as Fierke et al. U.S. Pat. 2,801,171, and Vittum et al. U.S. Pat. 2,801,170, both issued July 30, 1957, and Julian U.S. Pat. 2,949,360, issued Aug. 16, 1960, etc.

The organic solvents include:

(1) Low-boiling, substantially water-insoluble organic solvents, such as, methyl, ethyl, propyl, and butyl acetates, isopropyl acetate, ethyl propionate, sec-butyl alcohol, ethyl formate, butyl formate, nitromethane, nitroethane, carbon tetrachloride, chloroform, etc., and

(2) Water-soluble organic solvents, such as methyl isobutyl ketone, fi-ethoxyethyl acetate, tetrahydrofurfuryl adipate, Carbitol acetate (diethyleneglycol monoacetate), methoxytriglycol acetate, methyl Cellosolve acetate, acetonyl acetone, diacetone alcohol, butyl Carbitol, butyl Cellosolve, methyl Carbitol, methyl Cellosolve, ethylene glycol, diethylene glycol, dipropylene glycol, acetone, methanol, ethanol, acetonitrile, dimethylformamide, dioxane, etc.

Combinations of two or more of the new and improved dye-stabilizing agents of our invention may be used. These agents may also be used in combination with other addenda ino the same dispersion, for example, other stabilizing agents, antistain agents, e.g., ballasted hydroquinones,

6 phenolic antioxidants, etc. The selection of the specific stabilizer compound and the concentration used in each layer of a multilayer film can be varied over a wide range, and will depend on the improvement in resistance to fading required for each of the image dyes in the respective layers.

Any of the well-known primary aromatic amino colorforming silver halide developing agents such as the phenylenediamines, e.g., N,N-diethyl-p-phenylenediamine hydrochloride, N monomethyl p phenylenediamine hydrochloride, N,N dimethyl p phenylenediamine hydrochloride, 2 amino 5 diethylaminotoluene hydrochloride, 2 amino 5 (N-ethyl-N-laurylamino) toluene, N ethyl N B (methylsulfonamido)ethyl-3- methyl 4 aminoaniline sulfate, N ethyl N (5- methylsulfonamidoethyl) 4 aminoaniline, 4 (N- ethyl N ,6 hydroxyethyl)aminoaniline, etc., the paminophenols and their substitution products where the amino group is unsubstituted, e.g., 2,6-dichloro-4-aminophenol, 2 bromo p aminophenol, 2,6-diiodo-4-aminophenol, 4 aminophenol, etc., may be used to develop photographic coatings containing our stabilizers. Various other materials may be included in the developer solutions depending upon the particular requirements, for example, image-forming couplers competing couplers, antifoggants, hardeners, an alkali metal sulfite, bisulfite, alkaline buffer salts, bromide, iodide, etc., and the thickening agents used in viscous developer compositions. A typical developer solution is given in Example 1 but does not limit the invention.

Our stabilizers are incorporated in hydrophilic colloid layers intended for the storage of photographic dye images, such as, a receiving sheet for receiving a ditt'usible transferred dye image or a dye-image forming layer containing a light-sensitive material such as silver halide (e.g., silver chloride, silver bromide, silver iodide, silver chlorobromide, silver chlorobromoiodide, silver bromoiodide, etc.), a light-sensitive diazo compound (as in diazo-type material), etc.

Hydrophilic colloids used to advantage in the image layers include any of the hydrophilic colloids used in image-forming layers and in receiving layers, such as gelatin, and gelatin derivatives, casein and other proteinaceous colloids, hydrophilic cellulosic derivatives, e.g., carboxymethyl cellulose, alginates, synthetic resins, e.g., polyvinyl alcohol, copoly(ethylacrylate, acrylic acid) polyvinyl pyrrolidone, etc. Some colloids used to advantage are polyvinyl alcohol or a hydrolyzed polyvinyl acetate as described in U.S. Pat. 2,286,215, a far hydrolyzed cellulose ester, such as cellulose acetate hydrolyzed to an acetyl content of 1926%, as described in U.S. Pat. 2,327,808, a water-soluble ethanolamine cellulose acetate as described in U.S. lPat. 2,322,085, a polyacrylamide having a combined acrylamide content of 30-60% and a specific viscosity of 025-15 on an imidized polyacrylamide of like acrylamide content and viscosity as described in U.S. Pat. 2,541,474, zein as described in U.S. Pat. 2,563,791, a vinyl alcohol polymer containing urethane carboxylic acid groups of the type described in U.S. Pat. 2,768,154, or containing cyano-acetyl groups, such as the vinyl alcohol-vinyl cyanoacetate copolymer as described in U.S. Pat. 2,808,331, or a polymeric material which results from polymerizing a protein or a. saturated acylated protein with a monomer having a vinyl group as described in U.S. Pat. 2,852,382.

The emulsions used in the photographic element of our invention can be chemically or optically sensitized.

Our stabilizing compounds are also used to advantage with mordants in dye-image receiving sheets for dye diffusion transfer processes such as are described in French Pat. 75,676, dlivr June 19, 1 961. Mordant receiving sheets in which our compounds can be used to advantage are described in French Pat. 1,361,293, dlivr Apr. 6, 1964. When the dilfusible-image dyes are mordanted in such receiving sheets containing our stabilizer compounds, they exhibit marked improvement in light stability.

Usually emulsions containing our stabilizer compounds are coated on photographic supports in the form of multilayer color photographic elements wherein at least three differently sensitized emulsion layers are coated over one another on the support. Usually the support is coated in succession with a red-sensitive layer, a green-sensitive layer, and a blue-sensitive layer either with or without a Carey Lea filter layer between the blue-sensitive and green-sensitive layers. The three differently color sensitized layers may be arranged in any other order over one another that is desirable; however, the Carey Lea filter layer (i.e., yellow colloidal silver) would not be put over the blue-sensitive layer. Preferably, these light-sensitive layers are arranged on the same side of the support.

In general, our stabilizing agents are used in quantities ranging from 0.25 mole to 20 moles of stabilizer per 1 mole of coupler used (or per 1 mole of dye produced). The preferred range is from 1 mole to 5 moles of stabilizer per mole of coupler (or per mole of dye produced).

The following examples are included for a further understanding of our invention.

EXAMPLE 1 Six single layer coatings are made on a paper support of gelatino silver halide emulsions containing 80 mg./ft. of magenta dye-forming coupler No. 6 of US. Pat. 3,062,653 (i.e., 1 (2 chloro-4,6-dimethylphenyl)-3-{3- [a (3 pentadecylphenoxy)-butyramido]benzamido}-5- pyrazolone), 80 mg./ft. of coupler solvent tricresylphosphate, 320 mg./ft. of gelatin, and 160 mg./ft. of silver, and the amount of addenda indicated in Table I.

TABLE I Additional coupler solvent Compound Amount Coating number:

1, control None None None. 2 40 rug/ft)-.." A 40 rug/it. 3, control None None None. 4 40 mg./ft. B 40 mgJiL 2 5, control None None None. 6.. 40 rug/it. X. 40 rug/it.

Compound A is 7 t butyl 2,2 dimethyl 6 hydroxy- 4-isopropylchromanol (of French Pat. 1,478,141) Compound B is 7 t butyl 2,2,4 trimethyl 6 hydroxychromanol (of French Pat. 1,478,141) Compound X is 6 t butyl 2,2 dimethyl 5 hydroxy coumaran (of US. Pat. 2,535,058)

The coatings are exposed with a 1B intensity scale sensitometer and processed to color negatives using the following process.

Minutes Develop (formula below) l Kodak F-S fixing bath Water wash 5 Bleach (ferricyanide) 5 Water wash 5 Kodak F5 fixing bath 5 Water wash 10 Dry Developer formula:

An area having a magenta dye density of 1.2 is identified in each of the processed coatings which are then subjected to a 10 day northlight fading test (SANS, i.e., simulated average north sky light equivalent to 120,000 foot candle hours). The magenta dye loss at the identified areas having an original density of 1.2 is determined and listed in Table 2.

TABLE 2 Percent loss in Coating No.1 magenta dye density 1 47 The data show that compound X is unacceptable as a stabilizer for the magenta dye. From these data it is unexpected that our compounds would be good stabilizers.

EXAMPLE 2 Six single layer gelatinous coatings containing a pre formed magenta dye are made on a support. The coatings have the following compositions:

Tricresyl phosphate mg./ft.

Stabilizer compound indicated in Table 315 mole/ft. Gelatin733 mg./ft.

Triisopropylnaphthalene sulfonate-33 mg./ft. Saponin-ZS mg/ft.

The magenta dye is prepared by reacting the coupler, 1 (2 chloro 4,6 dimethylphenyl) 3 {3 [a (3- pentadecylphenoxy)butyramido] benzamido} 5 pyrazolone dissolved in tricresyl phosphate with the oxidized form of color developing agent, N ethyl ,8 methanesulfnoamidoethyl 3 methyl 4 aminoaniline sulfate. The coatings are subjected to SANS light fading test described in Example 1 but for 3 weeks. The stabilizer and the loss in magenta dye density (from an area of the dye image having an original magenta dye density of 1.2) are listed in Table 3.

Density loss from 3 weeks SANS exposure,

The data show that our stabilizer compounds produce up to an 88% improvement in the stability of the preformed magenta dye compared to the control when subjected to the 3 weeks SANS test.

Similar results are obtained when Example 2 is repeated using magenta dyes produced from the magenta coupler and the oxidized form of other well-known color developing agents including those disclosed herein previously. Similar results are obtained when Example. 2 is repeated using any of the other well-known magenta dyeforming couplers with the oxidized form of any of the well-known color-developing agents described herein previously.

EXAMPLE 3 Four single layer gelatinous silver halide emulsion coatings containing the magenta dye-forming coupler, 1-(2- chloro 4,6 dimethylphenyl) 3 {3 [a (3 pentadecylyphenoxy)butyramido] benzamido} 5 pyrazolone are made on a paper support. The gelatinous silver bromoiodide emulsion is prepared as described by Trivelli and Smith in the Photographic Journal, page 330, May 1939. The coatings have the following compositions:

TABLE 4 Coupler (identified above)50 mg./ft.

Tricre-syl phosphate-O mg./ft.

Stabilizer (as indicated in Table 5)equimolar to coupler Gelatin-440 IIlg./ft.

Triisopropylnaphthalene sulfonate20 mg./ft. Saponin-IS mg./ft.

The coatings are dried and given /2 second exposure on a 1B intensity scale sensitometer, followed by color processing at 75 F. as follows:

Min. Color development 6 Stop-fix bath 3 Wash 2 Ferricyanide bleach 4 Wash 3 Hardening fix 3 Wash 8 Buffer (stabilizer) 3 The color developer is a conventional color developer solution containing benzyl alcohol, sodium sulfite, the color developing agent, N ethyl 3 methanesulfonamidoethyl 3 methyl 4 aminoaniline sulfate and an alkali to give a pH of about 10. A conventional stop-fix bath containing sodium thiosulfate, sodium sulfite, acetic acid, boric acid and potassium alum is used for the stopfix step and for the hardening fix steps in the process. A conventional alkali metal ferricyanide-bromide bleach bath is used, and a conventional aqueous citric acid stabilizer bath having a pH of 3.5 is used in the process. An area having a magenta dye density of about 1.2 is identified on each processed coating before exposing them to a 3 weeks SANS fading test. The results are summarized in the following table.

The results show that our stabilizer Nos. 4 and 7 produce a substantial improvement in the stability of the magenta dye formed by color development in coating Nos. 3 and 4 compared to coating No. 2 containing prior art stabilizer 2,2,4-trimethyl-6-hydroxy-7t-octylchroman (compound No. 7 of French Pat. 1,478,141) for the 3 weeks SANS test.

EXAMPLE 4 Example 3 is repeated using magenta dye-forming S-pyrazolone couplers 1 through 12 of US. Pat. 2,600,788 in place of the coupler used in Example 3. The results are similar to those obtained in Example 3.

EXAMPLE 5 Example 3 is repeated using magenta dye-forming 5-pyrazolone couplers 6 through 9 of US. Pat. 2,908,573 in place of the coupler used in Example 3. The results are similar to those obtained in Example 3.

EXAMPLE 6 Example 3 is repeated using colored magenta dyeforming 5-pyrazolone couplers 1 through 5, 7 and 8 of US. Pat. 2,725,292, in place of the coupler used in Example 3. In this example the dye of the coupler remaining in the color processed layer as well as the magenta dye formed by coupler that coupled with oxidized color 10 developer during color processing are both stabilized against the destructive effects of prolonged exposure to light in the SANS fading test.

Similarly the valuable stabilizing effect of our stabilizing agents can be demonstrated for still other dyes particularly the dyes formed by chromogenic development of any of the known 5-pyrazolone couplers.

EXAMPLE 7 A gelatinous silver halide emulsion is prepared as described by Trivelli and Smith in The Photographic Jourrial, page 330, May 1939. One portion of this emulsion is coated as a control identified as coating No. 1 on a cellulose acetate film support. Coating No. 2 is made of another portion of the emulsion to which our stabilizing compound No. 4 is added so that it is coated at a rate of 10- mole (of stabilizer) per ft. Coating No. 3 is made of another portion of the emulsion to which our stabilizing compound N0. 4 is added so that it is coated at the same rate as stabilizing compound No. 4. The coatings are given a sensitometric exposure and color developed in a conventional magenta color developing solution containing the color developing agent, 4-amino-N-ethyl-N- (fl-methanesulfonamidoethyl) m toluidine sesquisulfate monohydrate, an alkali, an alkali metal sulfite and the magenta dye-forming coupler, 1-(2,4,6-trichlorophenyl)- 3-(2,4-dichloroanilino)-5-pyrazolone (coupler No. 6 of US. Pat. 3,152,896). The color developed coatings are then water washed, bleached in a conventional alkali metal ferricyanide-bromide bleach, fixed in a conventional alkali metal thiosulfate fixing bath washed and dried. Our stabilizer compounds 4 and 7 in coatings 2 and 3 impart valuable protection to the magenta dye images as is illustrated by 3 weeks SA-NS test as described in Example 2.

Similar results are obtained when Example 7 is repeated with other dye-stabilizing compounds of our invention and with other primary aromatic amine color developing agents and other magenta dye-forming couplers including couplers 1, 2, 3, 4, 5, 7 and 8 of US. Pat. 3,152,896 as well as other diffusible magenta dye-forming couplers well know in the art.

Our stabilizer compounds are advantageously incorporated in the receiving layer of image receiving sheets to stabilize the dye images transferred thereto. For example, image transfer dyes made from compounds I through XLVI of US. Pat. 3,227,551 and transferred to receiving layers containing our stabilizer compounds have improved stability to prolonged exposure to light. Similarly, dye images produced from dye developers such as those described in US. Pat. 3,404,002 and transferred to receiving layers containing our stabilizer compounds are found to fade less upon prolonged exposure to light than the same images transferred to a receiving layer containing none of our stabilizers.

Similarly, the azo dye images produced in silver dyebleach elements containing our stabilizers are substantially more stable to prolonged exposure to light than images that are not so protected. Thus our stabilizers are advantageously incorporated in silver dye-bleach materials, such as those described in US. Patents 2,418,624, 2,420,630, 2,420,631, etc.

Our stabilizing compounds are also advantageously incorporated in the azo dye image-forming layer of any of the diazo-type elements that are used for duplicating images. Thus our stabilizer compound is incorporated into the polymeric matrix layer containing the diazo salt(s) and coupler(s) where it advantageously protects the azo dye image produced upon development of the light image exposed layer.

In general the compounds of :Formula I in which Z represents a group are advantageously prepared by treating an enamine of the formula: I

II n

wherein R R R and R are as described previously with a quinone of the formula:

III

R4 Ra wherein R R and R are as described previously, according to the procedure described in Brannock et al. US. Pat. 3,184,457 issued May 18, 1965, incorporated herein as part of this application by reference. Compounds of Formula I in which Z represents an alkoxy group are advantageously prepared by reacting an enol ether compound of the formula:

We claim:

1. A hydrophilic colloid layer containing a color photographic dye image, said layer containing at least one nondiffusible S-hydroxycoumaran selected from the class consisting of a 2-amino-5-hydroxycoumaran and a 2- alkoxy-5-hydroxycoumaran.

2. A hydrophilic colloid layer containing a color photographic dye image, said layer containing at least one nondiffusible 5-hydroxycoumaran selected from the class consisting of those have the formula:

wherein R represents a member selected from the class consisting of hydrogen, an alkyl group, and the necessary atoms to complete with R a fully hydrogenated hydrocarbon ring having from 4 to 7 atoms in the ring; R represents a group selected from the class consisting of an alkyl group and the necessary atoms to complete with R a fully hydrogenated hydrocarbon ring having from 4 to 7 atoms in the ring; R represents a member selected from the class consisting of hydrogen, an alkyl group and an alkoxy group; R represents a member selected from the class consisting of hydrogen, an alkyl group, an alkoxy group and the necessary atoms to complete with R a saturated ring fused with the phenol ring; R represents a member selected from the class consisting of hydrogen, an

Corn ound Num ber of- Compound of Formulas II or IV Compound of Formula III Formula:

l l-morph olmoisobntylenm t-butylquinone.

2 l-(Nethoxyearhonyl-N-pip sobutylene D0.

(1 -plperidino) -2-ethylhex-l,2-ene -m ethylanilinohsobutena l-(N-butylanilino) propane 1- (Ndmeth ylanilino) isobutenet-octylquinone.

D o. t-bu tylquinone.

t-octylquinone.

t-butylquinone.

. t-octylquinone.

Do. t-butylquinone. 6-t-but0xy-2-methylquinone. 2-t-butyl-5-ethoxyquinone. 2-t-butyl-3-phenylquinone. 2-t-butyl-3-ethoxyquinone.

t-butylquinone.

10 0 1L l-(Nanethylanilino)-2-othylhex-1 ,2-cne 13... l-piperidinoisobutene 15-.. 1-(N-anilin0)isobutene 19 1-(N,N-dirnethylarnin0)iso 1,2,3A-tetrahydronaphthoqumono. 20, Ethylisobutenyl ether 1. l-(ethoxy) -2-ethylhex-l,2-ene t-octylqurnone. Ethyl isobutenyl ether... D0. 3. Butyl isobutenyl ether. t-butylqulnone. 24 Oetadecyl isobutenyl ether Docosyl isobutenyl ether g0- 26 2-methylpentyl isobutenyl ether The enamines of Formula II are advantageously prepared by the reaction of known secondary amines with known aliphatic aldehydes having at least one rat-hydrogen.

The enol ethers of Formula IV are derived from known aliphatic aldehydes having only one tat-hydrogen atom.

The quinones of Formula III are well known in the art and are either available or prepared by well known methods.

Our hydrophilic colloid layers containing dye images, such as, indophenol dye images, indoaniline dye images, azomethine dye images and azo dye images and a stabilizing amount of our nonalkyl-Z-alkoxy-S-hydroxycoumarans provide a valuable technical advance in color image re production because these images are substantially more N stable than the same images in layers containing no stabilizer or a prior art stabilizer.

The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

alkyl group, an alkoxy group, a mononuclear aryl group and the necessary atoms to complete with R a saturated ring fused with the phenol ring; Z represents a group selected from the class consisting of a group and an OR group; R represents a group selected from the class consisting of an alkyl group, an aryl group, a heterocyclic group having from 4 to 7 atoms in the ring and the necessary atoms to complete with R a heterocyclic ring having from 4 to 7 atoms in the ring; R represents a group selected from the class consisting of an alkyl group, an aryl group, a heterocyclic group having from 4 to 7 atoms in the ring and the necessary atoms to complete with R a heterocycic ring having from 4 to 7 atoms in the ring; and R represents an alkyl group.

13 3. A hydrophilic colloid layer of claim 2 in which the Z group in the S-hydroxycoumaran represents a group wherein R represents a group selected from the class consisting of an alkyl group, an aryl group, a heterocyclic group having from 4 to 7 atoms in the ring and the necessary atoms to complete with R; a heterocyclic ring having from 4 to 7 atoms in the ring; R represents a group selected from the class consisting of an alkyl group, an aryl group, a heterocyclic group having from 4 to 7 atoms in the ring and the necessary atoms to complete with R at heterocyclic ring having from 4 to 7 atoms in the ring.

4. A hydrophilic colloid layer of claim 2 in which the Z group in the S-hydroxycoumaran represents a --OR group in which R represents an alkyl group.

5. A dye image-forming layer comprising a film-forming hydrophilic colloid layer containing at least one nonditfusible, S-hydroxycoumaran selected from the class consisting of a Z-amino-S-hydroxycoumaran and a 2-alkoxy- 5-hydr0xycoumaran.

6. A dye image-forming layer of claim 5 in which the image-forming layer contains a silver halide emulsion.

7. A dye image-forming silver halide emulsion layer comprising a film-forming hydrophilic colloid layer containing at least one nondiffusible S-hydroxycoumaran selected from those having the formula:

l R2 HO- I R! wherein R represents a member selected from the class consisting of hydrogen, an alkyl group, and the necessary atoms to complete with R a fully hydrogenated hydrocarbon ring having from 4 to 7 atoms in the ring; R represents a group selected from the class consisting of an alkyl group and the necessary atoms to complete with R a fully hydrogenated hydrocarbon ring having from 4 to 7 atoms in the ring; R represents a member selected from the class consisting of hydrogen, an alkyl group and an alkoXy group; R represents a member selected from the class consisting of hydrogen, an alkyl group, an alkoxy group and the necessary atoms to complete with R a saturated ring fused with the phenol ring; R represents a member selected from the class consisting of hydrogen, an alkyl group, an alkoxy group, a mononuclear aryl group and the necessary atoms to complete with R; a saturated ring fused with the phenol ring; Z represents a group selected from the class consisting of a group and an O R group; R represents a group selected from the class consisting of an alkyl group, an aryl group, a heterocyclic group having from 4 to 7 atoms in the ring and the necessary atoms to complete with R a heterocyclic ring having from 4 to 7 atoms in the ring; R represents a group selected from the class consisting of an alkyl group, an aryl group, a heterocyclic group having from 4 to 7 atoms in the ring and the necessary atoms to complete with R a heterocyclic ring having from 4 to 7 atoms in the ring; and R represents an alkyl group.

8. A dye image-forming silver halide emulsion layer of claim 7 in which R represents the t-butyl group.

9. A dye image-forming silver halide emulsion layer of claim 7 in which R represents the t-octyl group.

10. A magenta dye image-forming silver halide emulsion layer containing 3,3-dimethyl5-hydroxy-2-(N-methylanilino)-6-t-octylcoumaran.

11. A magenta dye image-forming silver halide emulsion layer containing 2 (N-methylanilino)-6-t-butyl-3,3- dimethyl-S-hydroxycoumaran.

12. A magenta dye image forrning silver halide emulsion layer containing 2-(N-anilino)-6-t-butoxy-5-hydroxy- 3,3,4-trimethylcoumaran.

13. A magenta dye image-forming silver halide emulsion layer containing 6-t-butyl-3,3-dimethyl-5-hydroxy-2 morpholino coumaran.

14. A magenta dye image-forming silver halide emulsion layer containing 6-t-butyl-3,3-dimethyl-2-(N-ethoxycarbonyl-N-piperazino)-5-hydroxycoumaran.

15. A magenta dye image-forming silver halide emulsion layer containing 6-t-butyl-3,3dimethyl-2-(3-ethoxy carbonylpiperidino)-5-hydroxycoumaran.

16. In an element for color photography designed for dye image storage, said element comprising a support layer and at least one hydrophilic colloid layer for said dye image, the improvement comprising the use of a hydrophilic colloid layer containing a stabilizing amount of a nondiffusible, S-hydroxycoumaran selected from the class consisting of a 2-amino-5-hydr0xycoumaran and a 2- alkoxy-S-hydroxycoumaran for the said dye image.

References Cited UNITED STATES PATENTS 2,272,191 2/1942 Fierke 96-74 2,274,551 2/1942 Kenyon et al. 260l52 2,984,568 5/1961 Hart et al. 9684 2,535,058 12/1950 Gleim et al. 44-63 3,184,457 11/1966 Brannock et al. 260247.7 3,285,937 11/1966 Brannock et al. 260-3462 3,432,300 3/1969 Lestine et al. 9674 NORMAN G. TORCHIN, Primary Examiner r A. T. SURO PICO, Assistant Examiner US Cl. XJR. 96-77 

